GK 700RB di problem

Hi guys,
I recently purchased the GK 700RB 2X10 combo and I'm delighted with it, I use it mostly as backline/monitor going through a 2k rig, however I find when it comes to di'ing (using the xlr out from the amp) a very strange thing happens.

Basically when I use an xlr to xlr line out from the amp to the desk the amp seems to bypass all desk controls!!??? ie: even with the channel slider at 0 if I turn up the output volume from the di out on the amp I can control the master volume from the amp COMPLETELY bypassing the desk leaving the desk tone/eq controls redundant.

Now I've been playing a LOOONNGG time and I've NEVER come across this and in fairness it makes no logical sense for me to be able to control the channel on the desk from my amp, anyone else experience this from GK amps?? or is it a fault in mine??

I have NEVER heard of that one. I have a Allen and Heath board and I put my 1001 throught that thing all the time. Never does that. The board DOES have one channed that lets signal in even with the fader at 0. I just wiggle the fader to make it stop. Maybe, just maybe, it's the channel on the board.

Aside from having to adjust the DI output to the appropriate level, I've never had trouble running mine through a mixer into a PA (same mechanics involved I believe). I don't think that it's actually possible for the 700RB to cause this problem. It's just sending a signal. It has nothing to do with the attenuation on the board/desk amp. Perhaps that channel is bad?